Display devices such as television sets, PC displays, portable terminal displays and the like have a configuration wherein a display panel on which image display is carried out is electrically connected, by way of a mounted component, to an external connection component such as a printed wiring board (PWB) or a driving IC.
In response to the trend towards smaller and more lightweighted display devices in recent years, connection configurations have been proposed wherein a display panel and an external connection component are connected via a flexible printed board (flexible printed circuit: FPC) or a mounted component called a zebra connector.
A lightweight thin film having pliability, for instance a polyimide film or the like, can be used as the base material of an FPC. As a result, components can be mounted in a bent shape, and the mounting area can be reduced, which allows reducing the size and weight of the device. If the FPC is, for instance, a single-sided FPC in which a conductor is formed on only one of the faces of a base material, then a first connection terminal used for connection to a display panel and a second connection terminal used for connection to a printed circuit board are formed on the same face of the base material; then, with the substrate in a bent state, the first connection terminal can be connected to a terminal that is formed on the side of a thin film transistor array substrate (TFT array substrate) that makes up the display panel, while the second connection terminal can be connected to the printed circuit board through insertion into a connector.
The zebra connector can be connected to both the display panel and the printed circuit board that are disposed opposing each other, by being inserted between the display panel and the printed circuit board. This allows simplifying the mounting process and reducing costs. Herein, the printed circuit board is ordinarily disposed on the TFT array substrate side. Therefore, a color filter substrate (CF substrate) protrudes beyond the TFT array substrate, such that a terminal is formed at this protruding portion. A zebra connector is disposed between the CF substrate and the printed circuit board to elicit thereby the above-described connection.
Thus, the FPC must be connected on the TFT array substrate side, and the zebra connector must be connected on the CF substrate side. In current display panel designs, therefore, two types of display panel are produced, so as to support the type of the mounted component, namely display panels in which a connection terminal is formed on a TFT array substrate side and display panels in which a terminal region is formed on a CF substrate side. Accordingly, not only are two types of mask patterns necessary, namely a mask pattern for forming a terminal region on the TFT array substrate side, and a mask pattern for forming a terminal region on the CF substrate side, in accordance with the type of the mounted component, but also the display panel cannot accommodate modifications in the mounted component after the display panel has been produced.
Patent document 1 discloses a method for inexpensive connection of a display panel and an external connection component, wherein the method involves mounting a driver IC at a terminal region that is formed on a TFT array substrate side; and mounting an driver IC that is connected to a scanning-side electrode of a TFT array substrate, by drawing a terminal region, formed on a CF substrate side, onto a element glass, via a conductive layer; to reduce as a result the number of FPCs that are used to connect the display panel and the external connection component, and cut manufacturing costs accordingly.
Patent document 1: JP 11-223829 A
Depending on the type of a mounted component, however, there are cases, in the configuration of Patent document 1 above, where an external connection component is connected to a terminal region that is formed on a TFT array substrate side, and cases where a external connection component is connected to a terminal region that is formed on a CF substrate side. At present, thus, the terminal region is formed beforehand in either substrate depending on the type of mounted component to be used.